Z1OwnersClub GB

The standard (usual) Z1 has a 630 drive chain (92 links), with a 15 T front sprocket and a 35 T rear.
I'm fitting a 530 drive chain (110 links), with 18 T front sprocket and 42 T rear. The 530 chain (nowadays) is much stronger, the drive train is a lot smoother and lighter. This configurations maintains the same ratio.

I have one small problem, the supplier of front sprocket gave me a front sprocket without the small tab locking washer hole, but rather has two (diagonally opposite) tapped 6 mm holes. These holes are on a relatively large PCD.
I tried the larger locking nut , however, the spindle shaft seems too short to allow the locking part of the nut to lock. I don't want to buy another sprocket.

Anyone any ideas of how to lock this front sprocket? I believe this, two tapped holes method is used by other manufacturers (Hon*a) to retain the sprocket.
RegardZ.

They use a splined retainer that slips over the shaft splines and then rotates in a groove to "lock" it in place with the 6mm screws - no nut.

See if you can find (or make) a tab washer that locates on the splines then bends up to lock the nut.

you could try the lock washer from a er250/gpz 305 belt drive it is the type you are after + does not require a machined groove on the output shaft to locate it. the washer locates on the corners of the nut then is secured to the sprocket by 2 6mm bolts

kawasaki part no 13169-1742 PLATE,LOCK/ WASHER
cost is about £3

Thanks for the help Rich ...... Z1Bman, I'll look further into that belt drive sprocket/pulley holder..... I think the two 6 mm bolts may protrude too far out, touching the alloy casting of the Z1, where the chain oil pump is usually mounted on the Z1.

Home Made Tab Lock-washer for this 530 Sprocket

530 18 Tooth Sprocket

The Assembly

It was a pain in the ass to make this tab washer , however I now just have to lever up an edge to lock the nut into position

RegardZ.

good work garn should do the job. i would put some grease on the lock washer to prevent it from twisting when you tighten the nut